Artificial intelligence (AI) mimics or stimulates human behaviors or thinking to solve specific problems. It has been applied in the analysis of huge datasets and provides reliable outputs without human supervision in various online platforms, for example, information retrieval in search engines, digital assistants, voice assistants, digital marketing, personalized learning, social media, etc. This technology has provided many opportunities and challenges in line with strengthening the authenticity of the information provided via different search engines. This chapter reviews the current pieces of literature about the different AI algorithms used in the most popular metasearch engines and the application of artificial intelligence in these search engine contexts.